This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The ultimate goal of our work is to understand how the brain functions. To do this, we study the output (motor) portions, using the oculomotor system as a model. Specifically we study those fast movements known as saccadic eye movements. We continue our studies of mechanisms of saccade generation and have recently focused on the function of the caudal Fastigial nucleus (cFN). These studies represent a new direction for us and are still in early stages so no new publications have resulted in the current fiscal year. They consist of 3 related investigations to test whether the cFN is essential to the production of normal saccades. Our anticipated results will change fundamentally the way that we think saccades are produced. Not only will they improve our understanding of oculomotor processes but they may provide a new model for cerebellar function.They will not only advance our understanding of how the brain processes information in order to formulate actions based on that information, but they are also basic to the differential neurological diagnosis based on eye-movement signs now commonly used clinically. They also provide a foundation for studies of more complex aspects of central nervous system function such as interactions between motor systems (e.g., eye and head during orientation) or sensory and motor systems (e.g., the visual and oculomotor systems) and more abstract functions such as attention.